Data transmission method, access point, and station

ABSTRACT

When performing data transmission with a first station in a bandwidth power saving mode by using an operating channel of the first station, an access point performs data transmission with a second station by using an operating channel of the second station. Therefore, even if the operating channel of the first station includes a primary channel, the access point can still perform data transmission with the second station by using another channel. Further, for the access point, although the operating channel of the first station occupies only a part of available bandwidth resources of the access point, the access point can still perform data transmission with the second station by using a remaining channel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/862,434, filed on Apr. 29, 2020, which is a continuation of U.S.patent application Ser. No. 15/870,137, filed on Jan. 12, 2018, which isa continuation of International Application No. PCT/CN2015/084232, filedon Jul. 16, 2015. All of the afore-mentioned patent applications arehereby incorporated by reference in their entireties.

TECHNICAL FIELD

Embodiments of the present invention relate to the communications field,and in particular, to a data transmission method, an access point, and astation.

BACKGROUND

To meet a requirement of a large system throughput, a currentcommunications system forces all stations (STA) to support an 80 MHztransmission bandwidth mode. By using large bandwidth, a station cancomplete data transmission in a relatively short time, so as to reducedata transmission time and reduce data transmit power and receive power.However, when there is a relatively low requirement for uplink anddownlink data transmission, large bandwidth used for data transmissionis in an idle state for most of time. In this case, the station listensto a channel continuously, so that when there is an uplink or downlinkdata transmission requirement, the station determines, according to achannel status obtained by means of listening, whether data transmissioncan be performed. The channel status includes “channel idle” and“channel busy”. Undoubtedly, a process of continuously listening to arelatively wide channel greatly increases power consumption of thestation. In addition, an anti-interference capability of the station isweak.

Based on this, a method for dynamically adjusting bandwidth by a stationduring operating is introduced in the conventional art. Specifically,when there is a relatively low requirement for uplink and downlink datatransmission, the station switches the 80 MHz transmission bandwidthmode supported by the station to a bandwidth power saving mode (BWPSmode), and notifies, by sending an operating mode notification frame, anaccess point of a bandwidth mode currently supported by the station. Thebandwidth power saving mode refers to a bandwidth mode in whichavailable bandwidth of the station is less than 80 MHz (for example, theavailable bandwidth is 20 MHz, 40 MHz, or 60 MHz). In the bandwidthpower saving mode, a channel on which the station performs datatransmission includes a primary channel.

The foregoing method can reduce channel listening power consumption ofthe station to some extent when there is a relatively low requirementfor uplink and downlink data transmission. However, when data needs tobe transmitted between an access point and a station in a bandwidthpower saving mode, because the station in the bandwidth power savingmode occupies a primary channel, during communication with the stationoccupying the primary channel, the access point can perform datatransmission with this station only, and the access point can performdata transmission for the station only by using an operating channel ofthis station. Because the station is in the bandwidth power saving mode,for the access point, the operating channel of this station occupiesonly a part of available bandwidth resources of the access point, andall bandwidth resources except for the operating channel of this stationare wasted. This reduces resource utilization of the access point.

SUMMARY

This application provides a data transmission method, an access point,and a station, so as to resolve a problem that resource utilization ofan access point is low when a station in a bandwidth power saving modeoccupies a primary channel and during communication with the stationoccupying the primary channel, the access point can transmit data withthe station only.

To achieve the foregoing objective, this application provides thefollowing technical solutions.

A first aspect of this application provides a data transmission method,including:

performing, by an access point, data transmission with a first stationby using an operating channel of the first station, where the firststation enables a bandwidth power saving mode, and the operating channelof the first station is an available channel of the first station; and

when the access point performs data transmission with the first stationby using the operating channel of the first station, performing, by theaccess point, data transmission with a second station by using anoperating channel of the second station, where the operating channel ofthe first station and the operating channel of the second station formall or a part of available channels of the access point.

With reference to the first aspect, in a first implementation of thefirst aspect, before the performing, by an access point, datatransmission with the first station by using an operating channel of thefirst station, the method further includes: instructing, by the accesspoint, the first station to enable the bandwidth power saving mode,where

a process of the instructing, by the access point, the first station toenable the bandwidth power saving mode specifically includes:

sending, by the access point, first signaling, where the first signalingis used to instruct to enable the bandwidth power saving mode, andindicate a first channel set available to the first station, and totalbandwidth of channels in the first channel set is less than bandwidth ofthe available channels of the access point.

With reference to the first aspect, in a second implementation of thefirst aspect, before the performing, by an access point, datatransmission with the first station by using an operating channel of thefirst station, the method further includes:

receiving, by the access point, a request for enabling the bandwidthpower saving mode from the first station, where the request carries asecond channel set, the second channel set is an available channel,requested by the first station from the access point, in the bandwidthpower saving mode, and total bandwidth of channels in the second channelset is less than bandwidth of the available channels of the accesspoint; and

sending, by the access point, a request response to the first station,where the request response carries a third channel set, and totalbandwidth of channels in the third channel set is less than thebandwidth of the available channels of the access point.

With reference to the first aspect, the first implementation of thefirst aspect, or the second implementation of the first aspect, in athird implementation of the first aspect, the method further includes:

sending, by the access point, an update instruction to the station inthe bandwidth power saving mode, where the update instruction is used toindicate an updated channel set allocated by the access point to thestation in the bandwidth power saving mode, total bandwidth of channelsin the updated channel set is less than the bandwidth of the availablechannels of the access point, and the updated channel set is differentfrom a to-be-updated channel set of the station in the bandwidth powersaving mode.

With reference to the first aspect, the first implementation of thefirst aspect, the second implementation of the first aspect, or thethird implementation of the first aspect, in a fourth implementation ofthe first aspect, the performing, by an access point, data transmissionwith the first station by using an operating channel of the firststation includes:

receiving, by the access point by using the operating channel of thefirst station, data that starts to be sent by the first station at apreset sending time point, where the preset sending time point isspecified by the access point; and

the performing, by the access point, data transmission with a secondstation by using an operating channel of the second station includes:

receiving, by the access point by using the operating channel of thesecond station, data that starts to be sent by the second station at apreset sending time point, where

the operating channel of the first station is a subset of a channel setof the first station in the bandwidth power saving mode; when the secondstation enables the bandwidth power saving mode, the operating channelof the second station is a subset of a channel set of the second stationin the bandwidth power saving mode; and the operating channel of thefirst station and the operating channel of the second station do notoverlap.

With reference to the fourth implementation of the first aspect, in afifth implementation of the first aspect, before the performing, by anaccess point, data transmission with the first station by using anoperating channel of the first station, the method further includes:

sending, by the access point to the first station, a first trigger frameused to indicate the operating channel of the first station; and beforethe access point performs data transmission with the second station byusing the operating channel of the second station, sending, to thesecond station, a second trigger frame used to indicate the operatingchannel of the second station, where the first trigger frame is used totrigger the first station to start to send data at the preset sendingtime point, and the second trigger frame is used to trigger the secondstation to start to send data at the preset sending time point.

With reference to the first aspect, the first implementation of thefirst aspect, the second implementation of the first aspect, the thirdimplementation of the first aspect, the fourth implementation of thefirst aspect, or the fifth implementation of the first aspect, in asixth implementation of the first aspect, the performing, by an accesspoint, data transmission with the first station by using an operatingchannel of the first station includes:

sending, by the access point, a physical layer protocol data unit PPDUto the first station by using the operating channel of the firststation, where the PPDU includes service data, indication signaling usedto indicate a data receiving manner of the first station, a preambleused to indicate the operating channel of the first station, and controlsignaling used to indicate a data-sending resource of the first station;and

the performing, by the access point, data transmission with a secondstation by using an operating channel of the second station includes:

sending, by the access point, a PPDU to the second station by using theoperating channel of the second station, where the PPDU includes servicedata, indication signaling used to indicate a data receiving manner ofthe second station, and a preamble used to indicate the operatingchannel of the second station, where

the operating channel of the first station is a subset of the channelset of the first station in the bandwidth power saving mode; when thesecond station enables the bandwidth power saving mode, the operatingchannel of the second station is a subset of the channel set of thesecond station in the bandwidth power saving mode, and a subset of thechannel set of the second station in the bandwidth power saving mode isthe operating channel of the second station; and the operating channelof the first station and the operating channel of the second station donot overlap.

With reference to the first aspect, the first implementation of thefirst aspect, the second implementation of the first aspect, the thirdimplementation of the first aspect, the fourth implementation of thefirst aspect, the fifth implementation of the first aspect, or the sixthimplementation of the first aspect, in a seventh implementation of thefirst aspect, there is one or more second stations.

A second aspect of this application provides a data transmission method,including:

enabling, by a station, a bandwidth power saving mode; and

performing, by the station enabling the bandwidth power saving mode,data transmission with an access point by using an operating channel,where the operating channel is an available channel, in the bandwidthpower saving mode, of the station, and the access point is configured toperform, by using an operating channel of a second station, datatransmission with the second station when performing data transmissionwith the station, where the operating channel of the station and theoperating channel of the second station form all or a part of availablechannels of the access point.

With reference to the second aspect, in a first implementation of thesecond aspect, the enabling, by a station, a bandwidth power saving modeincludes:

sending, by the station, a request to the access point, where therequest carries a fourth channel set, and the fourth channel set is anavailable channel requested by the station from the access point, andtotal bandwidth of channels in the fourth channel set is less thanbandwidth of the available channels of the access point; and

receiving, by the station, a request response sent by the access point,where the request response carries a fifth channel set, and totalbandwidth of channels in the fifth channel set is less than thebandwidth of the available channels of the access point.

With reference to the second aspect, in a second implementation of thesecond aspect, the enabling, by a station, a bandwidth power saving modeincludes:

receiving, by the station, second signaling sent by the access point,where the second signaling is used to instruct the station to enable thebandwidth power saving mode, and indicate a sixth channel set availableto the station, and total bandwidth of channels in the sixth channel setis less than bandwidth of the available channels of the access point.

With reference to the second aspect, the first implementation of thesecond aspect, or the second implementation of the second aspect, in athird implementation of the second aspect, after the enabling, by astation, a bandwidth power saving mode, the method further includes:sending, by the station, an update request to the access point, wherethe update request carries a seventh channel set, total bandwidth ofchannels in the seventh channel set is less than the bandwidth of theavailable channels of the access point, and the seventh channel set isdifferent from a to-be-updated channel set of the station in thebandwidth power saving mode; and

receiving, by the station, a response returned by the access point forthe update request, where the response is used to instruct to change thechannel set of the station to the seventh channel set.

With reference to the second aspect, the first implementation of thesecond aspect, or the second implementation of the second aspect, in afourth implementation of the second aspect, after the enabling, by astation, a bandwidth power saving mode, the method further includes:

receiving, by the station, an update instruction sent by the accesspoint, where the update instruction is used to indicate an updatedchannel set allocated by the access point to the station, where totalbandwidth of channels in the updated channel is less than the bandwidthof the available channels of the access point, and the updated channelset is different from a to-be-updated channel set of the station in thebandwidth power saving mode.

A third aspect of this application provides an access point, including:

a first data transmission unit, configured to perform data transmissionwith a first station by using an operating channel of the first station,where the first station enables a bandwidth power saving mode, and theoperating channel of the first station is an available channel of thefirst station; and

a second data transmission unit, configured to: when data transmissionwith the first station is performed by using the operating channel ofthe first station, perform data transmission with a second station byusing an operating channel of the second station, where the operatingchannel of the first station and the operating channel of the secondstation form all or a part of available channels of the access point.

With reference to the third aspect, in a first implementation of thethird aspect, the access point further includes:

a signaling sending unit, configured to: before data transmission withthe first station is performed by using the operating channel of thefirst station, send first signaling to the first station, where thefirst signaling is used to instruct to enable the bandwidth power savingmode, and indicate a first channel set available to the first station,and total bandwidth of channels in the first channel set is less thanbandwidth of the available channels of the access point.

With reference to the third aspect, in a second implementation of thethird aspect, the access point further includes:

a receiving unit, configured to: before data transmission with the firststation is performed by using the operating channel of the firststation, receive a request for enabling the bandwidth power saving modefrom the first station, where the request carries a second channel set,the second channel set is an available channel, requested by the firststation from the access point, in the bandwidth power saving mode, andtotal bandwidth of channels in the second channel set is less thanbandwidth of the available channels of the access point; and

a responding unit, configured to send a request response to the firststation, where the request response carries a third channel set, andtotal bandwidth of channels in the third channel set is less than thebandwidth of the available channels of the access point.

With reference to the third aspect, the first implementation of thethird aspect, or the second implementation of the third aspect, in athird implementation of the third aspect, the access point furtherincludes:

an update instruction sending unit, configured to send an updateinstruction to the station in the bandwidth power saving mode, where theupdate instruction is used to indicate an updated channel set allocatedby the access point to the station in the bandwidth power saving mode,total bandwidth of channels in the updated channel set is less than thebandwidth of the available channels of the access point, and the updatedchannel set is different from a to-be-updated channel set of the stationin the bandwidth power saving mode.

With reference to the third aspect, the first implementation of thethird aspect, the second implementation of the third aspect, or thethird implementation of the third aspect, in a fourth implementation ofthe third aspect, that the first data transmission unit is configured toperform data transmission with the first station by using the operatingchannel of the first station includes:

the first data transmission unit is specifically configured to receive,by using the operating channel of the first station, data that starts tobe sent by the first station at a preset sending time point, where thepreset sending time point is specified by the access point; and that thesecond data transmission unit is configured to perform data transmissionwith the second station by using the operating channel of the secondstation includes:

the second data transmission unit is specifically configured to receive,by using the operating channel of the second station, data that startsto be sent by the second station at a preset sending time point, where

the operating channel of the first station is a subset of a channel setof the first station in the bandwidth power saving mode; when the secondstation enables the bandwidth power saving mode, the operating channelof the second station is a subset of a channel set of the second stationin the bandwidth power saving mode; and the operating channel of thefirst station and the operating channel of the second station do notoverlap.

With reference to the fourth implementation of the third aspect, in afifth implementation of the third aspect, the access point furtherincludes:

a trigger frame sending unit, configured to: before the first datatransmission unit performs data transmission with the first station byusing the operating channel of the first station, send, to the firststation, a first trigger frame used to indicate the operating channel ofthe first station; and before the second station transmission unitperforms data transmission with the second station by using theoperating channel of the second station, send, to the second station, asecond trigger frame used to indicate the operating channel of thesecond station, where the first trigger frame is used to trigger thefirst station to start to send data at the preset sending time point,and the second trigger frame is used to trigger the second station tostart to send data at the preset sending time point.

With reference to the third aspect, the first implementation of thethird aspect, the second implementation of the third aspect, the thirdimplementation of the third aspect, the fourth implementation of thethird aspect, or the fifth implementation of the third aspect, in asixth implementation of the third aspect, that the first datatransmission unit is configured to perform data transmission with thefirst station by using the operating channel of the first stationincludes:

the first data transmission unit is specifically configured to send aphysical layer protocol data unit PPDU to the first station by using theoperating channel of the first station, where the PPDU includes servicedata, indication signaling used to indicate a data receiving manner ofthe first station, a preamble used to indicate the operating channel ofthe first station, and control signaling used to indicate a data-sendingresource of the first station; and

that the second data transmission unit is configured to perform datatransmission with the second station by using the operating channel ofthe second station includes:

the second data transmission unit is specifically configured to send aPPDU to the second station by using the operating channel of the secondstation, where the PPDU includes service data, indication signaling usedto indicate a data receiving manner of the second station, and apreamble used to indicate the operating channel of the second station,where

the operating channel of the first station is a subset of the channelset of the first station in the bandwidth power saving mode; when thesecond station enables the bandwidth power saving mode, the operatingchannel of the second station is a subset of the channel set of thesecond station in the bandwidth power saving mode, and a subset of thechannel set of the second station in the bandwidth power saving mode isthe operating channel of the second station; and the operating channelof the first station and the operating channel of the second station donot overlap.

With reference to the third aspect, the first implementation of thethird aspect, the second implementation of the third aspect, the thirdimplementation of the third aspect, the fourth implementation of thethird aspect, the fifth implementation of the third aspect, or the sixthimplementation of the third aspect, in a seventh implementation of thethird aspect, that the second data transmission unit is configured toperform data transmission with the second station by using the operatingchannel of the second station includes:

the second data transmission unit is specifically configured to performdata transmission with the second station by using the operating channelof the second station, where there is one or more second stations.

A fourth aspect of this application provides a station, including:

a bandwidth power saving mode enabling unit, configured to enable abandwidth power saving mode, where

the station enabling the bandwidth power saving mode performs datatransmission with an access point by using an operating channel, wherethe operating channel is an available channel, in the bandwidth powersaving mode, of the station, and the access point is configured toperform, by using an operating channel of a second station, datatransmission with the second station when performing data transmissionwith the station, where the operating channel of the station and theoperating channel of the second station form all or a part of availablechannels of the access point.

With reference to the fourth aspect, in a first implementation of thefourth aspect, the bandwidth power saving mode enabling unit includes:

a request sending subunit, configured to send a request to the accesspoint, where the request carries a fourth channel set, the fourthchannel set is an available channel requested by the station from theaccess point, and total bandwidth of channels in the fourth channel setis less than bandwidth of the available channels of the access point;and

a receiving subunit, configured to receive a request response sent bythe access point, where the request response carries a fifth channelset, and total bandwidth of channels in the fifth channel set is lessthan the bandwidth of the available channels of the access point.

With reference to the fourth aspect, in a second implementation of thefourth aspect, that the bandwidth power saving mode enabling unit isconfigured to enable the bandwidth power saving mode includes:

the bandwidth power saving mode enabling unit is specifically configuredto receive second signaling sent by the access point, where the secondsignaling is used to instruct the station to enable the bandwidth powersaving mode, and indicate a sixth channel set available to the station,and total bandwidth of channels in the sixth channel set is less thanbandwidth of the available channels of the access point.

With reference to the fourth aspect, the first implementation of thefourth aspect, or the second implementation of the fourth aspect, in athird implementation of the fourth aspect, the station further includes:

an update request sending unit, configured to: after the station enablesthe bandwidth power saving mode, send an update request to the accesspoint, where the update request carries a seventh channel set, totalbandwidth of channels in the seventh channel set is less than thebandwidth of the available channels of the access point, and the seventhchannel set is different from a to-be-updated channel set of the stationin the bandwidth power saving mode; and

an update instruction receiving unit, configured to receive a responsereturned by the access point for the update request, where the responseis used to instruct to change the channel set of the station to theseventh channel set.

With reference to the fourth aspect, the first implementation of thefourth aspect, or the second implementation of the fourth aspect, in afourth implementation of the fourth aspect, the update instructionreceiving unit is further configured to:

after the station enables the bandwidth power saving mode, receive anupdate instruction sent by the access point, where the updateinstruction is used to indicate an updated channel set allocated by theaccess point to the station, total bandwidth of channels in the updatedchannel set is less than the bandwidth of the available channels of theaccess point, and the updated channel set is different from ato-be-updated channel set of the station in the bandwidth power savingmode.

According to the data transmission method provided in this application,an access point performs, by using an operating channel of a secondstation, data transmission with the second station when performing datatransmission with a first station in a bandwidth power saving mode byusing an operating channel of the first station. Even if the operatingchannel of the first station includes a primary channel, the accesspoint can still perform data transmission with the second station byusing another channel. Further, for the access point, although theoperating channel of the first station occupies only a part of availablebandwidth resources of the access point, the access point can stillperform data transmission with the second station by using anotherchannel. In this way, all bandwidth resources of the access point exceptfor the operating channel of the first station can also be used for datatransmission at the same time, improving resource utilization of theaccess point.

BRIEF DESCRIPTION OF DRAWINGS

To describe the technical solutions in the embodiments of the presentinvention or in the conventional art more clearly, the following brieflydescribes the accompanying drawings required for describing theembodiments or the conventional art. Apparently, the accompanyingdrawings in the following description show merely some embodiments ofthe present invention, and a person of ordinary skill in the art maystill derive other drawings from these accompanying drawings withoutcreative efforts.

FIG. 1 is a schematic diagram of a system in a WLAN deployment scenario;

FIG. 2 is a schematic flowchart of a data transmission method accordingto an embodiment of this application;

FIG. 3 is a schematic flowchart of another data transmission methodaccording to an embodiment of this application;

FIG. 4 is a schematic flowchart of another data transmission methodaccording to an embodiment of this application;

FIG. 5 is a schematic diagram of physical layer protocol data accordingto this application;

FIG. 6 is another schematic diagram of physical layer protocol dataaccording to this application;

FIG. 7 is a schematic structural diagram of an access point according toan embodiment of this application; and

FIG. 8 is a schematic structural diagram of a station according to anembodiment of this application.

DESCRIPTION OF EMBODIMENTS

Solutions of this application may be applied to a wireless local areanetwork (WLAN). Currently, a standard used by the WLAN is the Instituteof Electrical and Electronics Engineers (IEEE) 802.11 series. The WLANmay include multiple basic service sets (BSS), and network nodes in thebasic service sets are stations (STA).

A station includes an access point station, also known as an accesspoint (AP), and a non access point station (Non-AP STA). Each basicservice set may include one AP and multiple non-AP STAs associated withthe AP.

APs, with a typical coverage radius of tens to hundreds of meters, aremainly deployed inside a family, a building, and a campus. Certainly,APs may also be deployed outdoors. An AP, equivalent to a bridgeconnecting a wired network and a wireless network, is mainly used toconnect various wireless network clients together, and then connect thewireless network to an Ethernet. Specifically, the AP may be a terminaldevice or a network device having a wireless fidelity (WiFi) chip.Optionally, the AP may be a device that supports the 802.11ax standard.Further optionally, the AP may be a device that supports various WLANstandards such as 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a.

The non access point station may be a wireless communications chip, awireless sensor, or a wireless communications terminal, for example, amobile phone that supports WiFi communication, a tablet PC that supportsWiFi communication, a set top box that supports WiFi communication, asmart TV that supports WiFi communication, a smart wearable device thatsupports WiFi communication, an in-vehicle communications device thatsupports WiFi communication, and a computer that supports WiFicommunication. Optionally, the station can support the 802.11axstandard. Further optionally, the station supports various WLANstandards such as 802.11ac, 802.11n, 802.11g, 802.11b, and 802.11a.

FIG. 1 is a schematic diagram of a system in a typical WLAN deploymentscenario, in which one AP and three STAs are included, and the APperforms communication with a STA1, a STA2, and a STA3 separately. Inthe system, maximum bandwidth supported by the access point is greaterthan maximum bandwidth supported by a station in a power saving mode.For example, if the maximum bandwidth supported by the station in thepower saving mode is 20 MHz, the maximum bandwidth supported by theaccess point may be 40 MHz, 80 MHz, 160 MHz, or the like. For a stationin a non-power saving mode, maximum bandwidth supported by the stationis not greater than the maximum bandwidth supported by the access point,but is greater than the maximum bandwidth supported by the station inthe power saving mode. For example, if the maximum bandwidth supportedby the station in the power saving mode is 20 MHz, and the maximumbandwidth supported by the access point may be 80 MHz or 160 MHz, themaximum bandwidth supported by the station in the non-power saving modemay be 80 MHz or 160 MHz, or the like.

The following clearly describes the technical solutions in theembodiments of the present invention with reference to the accompanyingdrawings in the embodiments of the present invention. Apparently, thedescribed embodiments are merely a part rather than all of theembodiments of the present invention. All other embodiments obtained bya person of ordinary skill in the art based on the embodiments of thepresent invention without creative efforts shall fall within theprotection scope of the present invention.

Embodiment 1

An embodiment of this application provides a data transmission method.As shown in FIG. 2, the method includes the following steps.

S201. An access point performs data transmission with a first station byusing an operating channel of the first station, where the first stationenables a bandwidth power saving mode, and the operating channel is anavailable channel of the first station.

S202. When the access point performs data transmission with the firststation by using the operating channel of the first station, the accesspoint performs data transmission with a second station by using anoperating channel of the second station, where the operating channel ofthe first station and the operating channel of the second station formall or a part of available channels of the access point. Data mentionedin the present invention includes a combination (convergence) of one ormore of data from a MAC layer and an upper layer, a MAC-layer managementframe, and a MAC-layer control frame.

The first station in this embodiment is a station that enables abandwidth power saving mode. The bandwidth power saving mode means thatmaximum available transmission bandwidth is less than availabletransmission bandwidth of a system. For example, if transmissionbandwidth of the system is 80 MHz, transmission bandwidth in thebandwidth power saving mode may be 20 MHz, 40 MHz, or 60 MHz. Certainly,this is not limited thereto. That is, the available transmissionbandwidth of the station that enables the bandwidth power saving mode isless than the available transmission bandwidth of the system.

The data transmission in this embodiment includes data receiving andsending. Accordingly, that the access point performs data transmissionwith the first station by using the operating channel includes: theaccess point receives, by using the operating channel, uplink data sentby the first station, and the access point sends, by using the operatingchannel, downlink data to the first station. Similarly, that the accesspoint performs data transmission with the second station by using aremaining channel includes: the access point receives, by using theremaining channel, uplink data sent by the second station, and theaccess point sends, by using the remaining channel, downlink data to thesecond station. A specific uplink or downlink transmission process isdescribed in the following embodiments.

In this embodiment, there may be one or more second stations. When thereare multiple second stations, and when the operating channel of thefirst station and the operating channels of the second stations are apart of available channels of the access point, the access point canperform, by using another channel, data transmission with another secondstation at the same time when transmitting data to the first station andone second station. A quantity of second stations may be jointlydetermined according to an amount of data that can be transmitted byusing bandwidth of a system channel and an amount of data that istransmitted between the access point and the station.

In this embodiment, the second station may enable the bandwidth powersaving mode or may not enable the bandwidth power saving mode.

According to the data transmission method provided in this embodiment ofthe present invention, when performing data transmission with a firststation in a bandwidth power saving mode by using an operating channelof the first station, an access point performs data transmission with asecond station by using an operating channel of the second station. Thatis, the operating channel of the second station is another channeldifferent from the operating channel of the first station. Therefore,even if the operating channel of the first station includes a primarychannel, the access point can still perform data transmission with thesecond station by using the another channel. Further, for the accesspoint, although the operating channel of the first station occupies onlya part of available bandwidth resources of the access point, the accesspoint can still perform data transmission with the second station byusing another channel, so that all bandwidth resources of the accesspoint except for the operating channel of the first station can also beused for data transmission at the same time. This improves resourceutilization of the access point.

Embodiment 2

An embodiment of this application provides another data transmissionmethod. In this embodiment, further descriptions are provided from theperspective of uplink transmission. Specifically, as shown in FIG. 3,the method includes the following steps.

S301. An access point sends first signaling to a first station, wherethe first signaling is used to instruct the first station to enable abandwidth power saving mode, and indicate a first channel set availableto the first station, and total bandwidth of channels in the firstchannel set is less than bandwidth of an available channel of the accesspoint.

When battery power of a station is relatively low, an application layerinstructs the station to enable the bandwidth power saving mode, anamount of uplink or downlink data is reduced, or multiple channelsreceive great interference, and only some channels are in goodconditions, the access point can initiate a process for controlling thestation to enable the bandwidth power saving mode, and the stationenabling the bandwidth power saving mode listens to and/or transmitsdata only on a channel set (such as the first channel set) that has beenagreed by the station with the access point.

In this embodiment, the first signaling may carry an identifier of thefirst station, and there is a one-to-one correspondence between theidentifier of the first station and the first channel set. Afterreceiving the first signaling, the first station determines, accordingto the correspondence between the identifier of the first station andthe first channel set and the identifier of the first station, the firstchannel set indicated by the first signaling.

It should be noted that, when the access point controls the firststation to enable the bandwidth power saving mode, the access point mayconsider, without obtaining an acknowledgment ACK from the firststation, that the first station has enabled the bandwidth power savingmode and performed data transmission with the access point by using anoperating channel of the first station. The reason is that even if thefirst station has not successfully enabled the bandwidth power savingmode as instructed by the access point, the access point can stillperform data transmission with the first station normally.

S302. The access point controls a second station to enable the bandwidthpower saving mode. Specifically, for a control manner, reference may bemade to S301.

That is, the second station in this embodiment is also a station in thebandwidth power saving mode. In this embodiment, the access pointperforms data transmission with two stations in the bandwidth powersaving mode at the same time.

As described in the foregoing embodiment, when the access point alsoperforms data transmission with another station by using anotherchannel, if the another station is a station in the bandwidth powersaving mode, the first signaling may also carry an identifier of theanother station. If the another station includes multiple stations andthe multiple stations are group stations, the first signaling may carrya group address of the group stations. Certainly, the first signalingmay alternatively carry a broadcast address, and the broadcast addressis corresponding to all stations served by the access point.

It should be noted that an execution sequence of step S301 and step S302is not limited. That is, step S301 may be performed before step S302, ormay be performed after step S302.

S303. The access point sends, to the first station, a first triggerframe used to indicate an operating channel of the first station, andsends, to the second station, a second trigger frame used to indicate anoperating channel of the second station.

The first trigger frame is used to trigger the first station to start tosend data at a preset sending time point, and the second trigger frameis used to trigger the second station to start to send data at a presetsending time point. The operating channel of the first station is asubset of the first channel set. The operating channel of the firststation and the operating channel of the second station are a part orall of available channels of the access point.

A trigger frame in this embodiment is used to trigger a station to senduplink data, and the trigger frame implements time alignment for sendingof the uplink data by indicating start times of data sending to thefirst station and the second station.

In this embodiment, the first channel set that the access pointallocates to the first station may be the same as or different from achannel set that the access point allocates to the second station.However, regardless of whether the two channel sets are the same, whenan FDMA manner (frequency division multiple access, such as an OFDMAmanner) is used, to avoid collision between two stations during datasending, operating channels based on the two channel sets should notoverlap. When another manner (such as MU-MIMO) is used, channels of thetwo channel sets can overlap.

A subset of a channel set in this embodiment includes a channel set or apart of a channel set.

S304. The first station starts to send data to the access point at apreset sending time point by using the operating channel of the firststation.

S305. The second station starts to send data to the access point at apreset sending time point by using the operating channel of the secondstation.

It should be noted that an execution sequence of step S304 and step S305is not limited. That is, step S304 may be performed before step S305, ormay be performed after step S305.

S306. The access point sends an update instruction to a station in abandwidth power saving mode, where the update instruction is used toinstruct the access point to allocate an updated channel set to thestation in the bandwidth power saving mode, total bandwidth of channelsin the updated channel set is less than the bandwidth of the availablechannel of the access point, and the updated channel set is differentfrom a to-be-updated channel set of the station in the bandwidth powersaving mode.

In this embodiment, the update instruction is used to update a powersaving mode of the station. Regardless of the first station or thesecond station, a to-be-updated channel set is different from an updatedchannel set, which specifically includes:

when total bandwidth of channels in the to-be-updated channel set isdifferent from total bandwidth of channels in the updated channel set,the channels in the to-be-updated channel set are completely differentfrom the channels in the updated channel set; and/or

the channels in the to-be-updated channel set overlap with the channelsin the updated channel set; and/or

the channels in the to-be-updated channel set are exactly the same asthe channels in the updated channel set.

when the total bandwidth of the channels in the to-be-updated channelset is the same as the total bandwidth of the channels in the updatedchannel set, the channels in the to-be-updated channel set arecompletely different from the channels in the updated channel set;and/or

the channels in the to-be-updated channel set overlap with the channelsin the updated channel set.

It should be noted that, in this embodiment, that A overlaps with Bmeans only that there is an intersection of A and B.

For the foregoing cases of the channel sets before and after beingupdated, an example is provided for description.

Assuming that the available bandwidth of the access point is 80 MHz, theavailable bandwidth may be divided into four channels: a channel 1, achannel 2, a channel 3, and a channel 4. The channel 1 may be dividedinto a sub-channel 1 and a sub-channel 2. Each channel occupiesbandwidth of 20 MHz, and each sub-channel occupies bandwidth of 10 MHz.

If the channel set before being updated includes the channel 1, theupdated channel set may include the channel 3 and the channel 4 whenchannel bandwidth corresponding to the channel set before being updatedis different from channel bandwidth corresponding to the updated channelset. This is a case in which the channels are completely different.

The updated channel set may alternatively include the channel 1 and thechannel 2. In this case, the channels overlap, and an overlappingchannel is the channel 2.

The updated channel set may alternatively include the sub-channel 1 ofthe channel 1. In this case, the channels are exactly the same (that is,all the channels are the channel 1).

It is assumed that the channel set before being updated includes thechannel 1 and the channel 2.

When channel bandwidth corresponding to the channel set before beingupdated is the same as channel bandwidth corresponding to the updatedchannel set, the updated channel set may include the channel 3 and thechannel 4; and/or

the updated channel set may include the channel 2 and the channel 3, andan overlapping channel is the channel 2.

In this embodiment, the first station and the second station are bothstations in the bandwidth power saving mode. The access point sends atrigger frame to the first station and the second station, where thetrigger frame is used to trigger the first station and the secondstation to start to send data at a preset time, so as to implement timealignment for sending uplink data by the first station and the secondstation. In addition, because the operating channel of the first stationdoes not overlap with the operating channel of the second station, theaccess point in this embodiment can simultaneously control hybridsending of uplink data of two stations in the bandwidth power savingmode. This improves resource utilization of the access point.

After the first channel set is predetermined, the first station may senddata to and receive data from the access point for many times.

It can be learned from the foregoing steps that, in this embodiment,when performing communication with a station in a bandwidth power savingmode, an access point may also perform communication with anotherstation by using a remaining channel. In this way, resource utilizationof the access point can be improved.

Embodiment 3

An embodiment of this application provides still another datatransmission method. In this embodiment, descriptions are provided fromthe perspective of downlink transmission. Specifically, as shown in FIG.4, the method includes the following steps.

S401. A first station sends a request to an access point, where therequest carries a fourth channel set, where the fourth channel set is anavailable channel requested by a station enabling a bandwidth powersaving mode from the access point, and total bandwidth of channels inthe fourth channel set is less than bandwidth of the available channelof the access point.

The available channel may be represented by using a channel number, anindication of a position offset from a primary channel of a currentaccess point, or a center frequency and bandwidth of the channel.

Herein, it should be noted that the channel set requested by the stationfrom the access point is the same as a channel set carried in a requestreceived by the access point. For the “second channel set”, “thirdchannel set”, and “fourth channel set” used in this application, “Xth”is only for clarity of description. In a scenario in which the accesspoint interacts with the station, a channel set sent by a sender is achannel set received by a receiver.

S402. The access point sends a request response, where the requestresponse carries a fifth channel set, and total bandwidth of channels inthe fifth channel set is less than the bandwidth of the availablechannel of the access point.

In this embodiment, a process in which the first station enables a powersaving mode is initiated by the first station itself. In this case, thefirst station can perform, only after receiving a request responsereturned by the access point, data transmission with the access pointaccording to the channel set carried in the response.

In this embodiment, although a channel set requested by the firststation in the request is the fourth channel set, based on a loadbalancing consideration, a channel set returned by the access point inresponse to the first station is not necessarily the fourth channel set.That is, in this case, the fourth channel set is different from thefifth channel set. For example, when a load on a channel correspondingto the fourth channel set is excessively heavy and a load on a channelcorresponding to the fifth channel set is relatively light, the channelset returned by the access point in response to the first station is thefifth channel set.

Certainly, when the fourth channel set requested by the first stationsatisfies the load balancing consideration of the access point, thefifth channel set returned by the access point in response to the firststation is the same as the fourth channel set. That is, in this case,the access point agrees on the fourth channel set requested by the firststation, and the fifth channel set in the request response fed back bythe access point is the fourth channel set.

S403. The access point sends a physical layer protocol data unit PPDU tothe first station by using an operating channel of the first station.

In this embodiment, as shown in FIG. 5, the PPDU includes service data,indication signaling (signaling A and signaling B) used to indicate adata receiving manner of the first station, a preamble used to indicatethe operating channel of the first station, and control signaling usedto indicate a data-sending resource of the first station. Specifically,the preamble may be a compatible preamble. Different signaling Binformation may be transmitted over different 20 MHz channels.

Operating channel indication information of the first station includedin the preamble that is sent by the access point to the first stationand that is used to indicate the operating channel of the first stationis transmitted in the first channel set. Some preamble signalstransmitted by the access point may be transmitted over a channel not inthe first channel set, to serve users that perform transmission by usingthe channel not in the first channel set.

S404. The access point sends the PPDU to the second station by using anoperating channel of the second station.

When the first station occupies a primary channel, to allow the secondstation to receive control information, specifically, as shown in FIG.6, the PPDU sent to the second station includes service data, indicationsignaling used to indicate a data receiving manner of the secondstation, and a preamble used to indicate the operating channel of thesecond station, where indication information, that is, a beacon frame,may be carried in the operating channel of the second station.

Specifically, in this embodiment, the operating channel of the firststation is a subset of a channel set of the first station in thebandwidth power saving mode; when the second station enables thebandwidth power saving mode, the operating channel of the second stationis a subset of a channel set of the second station in the bandwidthpower saving mode; and the operating channel of the first station andthe operating channel of the second station do not overlap.

S405. The first station sends an update request to the access point,where the update request carries a seventh channel set, the seventhchannel set is an updated channel set that is requested by the stationin the bandwidth power saving mode from the access point, totalbandwidth of channels in the seventh channel set is less than thebandwidth of the available channel of the access point, and the seventhchannel set is different from a to-be-updated channel set of the stationin the bandwidth power saving mode.

Certainly, the second station can also request an update, and detailsare not described herein again.

S406. The access point sends an instruction in response to the updaterequest, where the instruction is used to instruct to change a channelset of the station to the seventh channel set.

It should be noted that an execution sequence of step S403 and step S404is not limited. That is, step S403 may be performed before step S404, ormay be performed after step S404.

In addition, in this embodiment, although an update for the bandwidthpower saving mode of the first station is initiated by the firststation, for a relationship between the channel sets before and afterbeing updated, reference may be made to the previous embodiment.

In this embodiment, the first station is a station in the bandwidthpower saving mode, and the second station is a station in a nonbandwidth power saving mode. The access point sends a preamble to thefirst station and the second station, where the preamble is used toindicate operating channels for receiving downlink data by the firststation and the second station, and the operating channel of the firststation and the operating channel of the second station do not overlap.In this way, the access point can send downlink data to multiplestations at the same time, improving resource utilization of a node.

It should be noted that, for the data transmission methods shown in FIG.3 and FIG. 4, in FIG. 3, the access point controls a station to enablethe bandwidth power saving mode (S301 and S302), and in FIG. 4, astation proactively requests to enable the bandwidth power saving mode(S401 and S402). The two manners are interchangeable, and neither manneris limited to be forcedly applied to the uplink or downlink scenariodescribed in the foregoing embodiments. Similarly, the update for thebandwidth power saving mode of a station may be initiated by the accesspoint (S306), or may be initiated by the station proactively (S405). Thetwo manners are interchangeable, and neither manner is limited to beforcedly applied to the uplink or downlink scenario described in theforegoing embodiments.

Embodiment 4

Corresponding to the embodiments of the data transmission method, asshown in FIG. 7, an embodiment of this application provides an accesspoint, including:

a first data transmission unit 710, configured to perform datatransmission with a first station by using an operating channel of thefirst station, where the first station enables a bandwidth power savingmode, and the operating channel of the first station is an availablechannel of the first station; and a second data transmission unit 720,configured to: when data transmission with the first station isperformed by using the operating channel of the first station, performdata transmission with a second station by using an operating channel ofthe second station, where the operating channel of the first station andthe operating channel of the second station form all or a part ofavailable channels of the access point.

Optionally, the access point provided in this embodiment may furtherinclude:

a signaling sending unit 730, configured to: before data transmissionwith the first station is performed by using the operating channel ofthe first station, send first signaling to the first station, where thefirst signaling is used to instruct to enable the bandwidth power savingmode, and indicate a first channel set available to the first station,and total bandwidth of channels in the first channel set is less thanbandwidth of the available channels of the access point;

a receiving unit 740, configured to: before data transmission with thefirst station is performed by using the operating channel of the firststation, receive a request for enabling the bandwidth power saving modefrom the first station, where the request carries a second channel set,the second channel set is an available channel, requested by the firststation from the access point, in the bandwidth power saving mode, andtotal bandwidth of channels in the second channel set is less than thebandwidth of the available channels of the access point; and

a responding unit 750, configured to send a request response to thefirst station, where the request response carries a third channel set,and total bandwidth of channels in the third channel set is less thanthe bandwidth of the available channels of the access point.

The signaling sending unit is configured for the access point toproactively control a station to enable the bandwidth power saving mode,and the receiving unit and the responding unit are configured tocooperate with the station when the station proactively triggersenabling of the bandwidth power saving mode.

Optionally, the access point provided in this embodiment may furtherinclude: an update instruction sending unit 760, configured to send anupdate instruction to a station in the bandwidth power saving mode,where the update instruction is used to indicate an updated channel setallocated by the access point to the station in the bandwidth powersaving mode, total bandwidth of channels in the updated channel set isless than the bandwidth of the available channels of the access point,and the updated channel set is different from a to-be-updated channelset of the station in the bandwidth power saving mode.

Optionally, to adapt to uplink data transmission, in this embodiment,the access point may further include:

a trigger frame sending unit 770, configured to: before the first datatransmission unit performs data transmission with the first station byusing the operating channel of the first station, send, to the firststation, a first trigger frame used to indicate the operating channel ofthe first station; and before the second station transmission unitperforms data transmission with the second station by using theoperating channel of the second station, send, to the second station, asecond trigger frame used to indicate the operating channel of thesecond station, where the first trigger frame is used to trigger thefirst station to start to send data at a preset sending time point, andthe second trigger frame is used to trigger the second station to startto send data at a preset sending time point.

During uplink transmission, a specific implementation in which the firstdata transmission unit performs data transmission with the first stationby using the operating channel of the first station may be: receiving,by using the operating channel of the first station, data that starts tobe sent by the first station at a preset sending time point, where thepreset sending time point is specified by the access point. A specificimplementation in which the second data transmission unit performs datatransmission with the second station may be: receiving, by using theoperating channel of the second station, data that starts to be sent bythe second station at a preset sending time point.

The operating channel of the first station is a subset of a channel setof the first station in the bandwidth power saving mode; when the secondstation enables the bandwidth power saving mode, the operating channelof the second station is a subset of a channel set of the second stationin the bandwidth power saving mode; and the operating channel of thefirst station and the operating channel of the second station do notoverlap.

During downlink transmission, a specific implementation in which thefirst data transmission unit performs data transmission with the firststation by using the operating channel of the first station may be:sending a PPDU to the first station by using the operating channel ofthe first station, where the PPDU includes service data, indicationsignaling used to indicate a data receiving manner of the first station,a preamble used to indicate the operating channel of the first station,and control signaling used to indicate a data-sending resource of thefirst station. A specific implementation in which the second datatransmission unit performs data transmission with the second station byusing a remaining channel may be: sending a PPDU to the second stationby using the operating channel of the second station, where the PPDUincludes service data, indication signaling used to indicate a datareceiving manner of the second station, and a preamble used to indicatethe operating channel of the second station.

The operating channel of the first station is a subset of a channel setof the first station in the bandwidth power saving mode; when the secondstation enables the bandwidth power saving mode, the operating channelof the second station is a subset of a channel set of the second stationin the bandwidth power saving mode; and the operating channel of thefirst station and the operating channel of the second station do notoverlap. Optionally, in this embodiment, there may be one or more secondstations that perform data transmission with the access point.

When performing communication with a station in a bandwidth power savingmode, the access point provided in this embodiment of the presentinvention can still perform data transmission with another station byusing a remaining channel. In this way, all bandwidth resources of theaccess point except for the operating channel of the station in thebandwidth power saving mode can also be used for data transmission,improving resource utilization of the access point.

Embodiment 5

An embodiment of this application further provides a station, including:

a bandwidth power saving mode enabling unit, configured to enable abandwidth power saving mode.

The station enabling the bandwidth power saving mode performs datatransmission with an access point by using an operating channel, wherethe operating channel is an available channel, in the bandwidth powersaving mode, of the station, and the access point is configured toperform, by using an operating channel of a second station, datatransmission with the second station when performing data transmissionwith the station, where the operating channel of the station and theoperating channel of the second station form all or a part of availablechannels of the access point.

As shown in FIG. 8, the bandwidth power saving mode enabling unit mayspecifically include:

a request sending subunit 810, configured to send a request to theaccess point, where the request carries a fourth channel set, the fourthchannel set is an available channel requested by the station enablingthe bandwidth power saving mode from the access point, and totalbandwidth of channels in the fourth channel set is less than bandwidthof the available channels of the access point; and a receiving subunit820, configured to receive a request response sent by the access point,where the request response carries a fifth channel set, and totalbandwidth of channels in the fifth channel set is less than thebandwidth of the available channels of the access point.

Alternatively, a specific implementation in which the bandwidth powersaving mode enabling unit enables the bandwidth power saving mode maybe: receiving second signaling sent by the access point, where thesecond signaling is used to instruct the station to enable the bandwidthpower saving mode, and indicate a sixth channel set available to thestation, and total bandwidth of channels in the sixth channel set isless than the bandwidth of the available channels of the access point.

Optionally, the station provided in this embodiment may further include:

an update request sending unit 830, configured to: after the stationenables the bandwidth power saving mode, send an update request to theaccess point, where the update request carries a seventh channel set,total bandwidth of channels in the seventh channel set is less than thebandwidth of the available channels of the access point, and the seventhchannel set is different from a to-be-updated channel set of the stationin the bandwidth power saving mode; and an update instruction receivingunit 840, configured to receive a response returned by the access pointfor the update request, where the response is used to instruct to changethe channel set of the station to the seventh channel set.

Further, the update instruction receiving unit may be further configuredto: after the station enables the bandwidth power saving mode, receivean update instruction sent by the access point, where the updateinstruction is used to indicate an updated channel set allocated by theaccess point to the station, total bandwidth of channels in the updatedchannel set is less than the bandwidth of the available channels of theaccess point, and the updated channel set is different from theto-be-updated channel set of the station in the bandwidth power savingmode.

In this embodiment, when performing data transmission with a station ina bandwidth power saving mode by using an operating channel of thestation, an access point performs data transmission with another stationby using another operating channel. That is, in the solution of thisapplication, the access point can perform data transmission for astation in a bandwidth power saving mode and another station at the sametime. That is, for the access point, although an operating channel ofthe station occupies only a part of available bandwidth resources of theaccess point, the access point can still perform data transmission withthe another station by using a remaining channel. In this way, allbandwidth resources of the access point except for the operating channelof the station can also be used for data transmission at the same time,improving resource utilization of the access point side. In addition, achannel that is used by the access point to perform data transmissionwith the another station is a remaining channel different from theoperating channel that is used by the access point to perform datatransmission with the station. Therefore, even if the operating channelof the station includes a primary channel, the access point can stillperform data transmission with the another station by using theremaining channel.

If the functions of the method in the embodiment are implemented in theform of a software functional unit and sold or used as an independentproduct, the functions may be stored in a computing device-readablestorage medium. Based on such an understanding, the part of theembodiments of the present invention contributing to the conventionalart or some of the technical solutions may be implemented in a form of asoftware product. The software product is stored in a storage medium,and includes several instructions for instructing a computing device(which may be a personal computer, a server, or a network device) toperform all or some of the steps of the methods described in theembodiments of the present invention. The foregoing storage mediumincludes: any medium that can store program code, such as a USB flashdrive, a removable hard disk, a read-only memory (ROM), a random accessmemory (RAM), a magnetic disk, or an optical disc.

The embodiments in this specification are all described in a progressivemanner, for same or similar parts in the embodiments, reference may bemade to these embodiments, and each embodiment focuses on a differencefrom other embodiments.

The embodiments disclosed above are described to enable a person skilledin the art to implement or use the present invention. Variousmodifications to the embodiments are obvious to the person skilled inthe art, and general principles defined in this specification may beimplemented in other embodiments without departing from the scope of thepresent invention. Therefore, the present invention is not intended tobe limited to these embodiments illustrated in this specification, butshall be construed in the widest scope consistent with the principlesand novel features disclosed in this specification.

What is claimed is:
 1. A data transmission method comprising: sending,by a first station (STA), a first frame to an access point (AP), whereinthe first frame comprises a first channel set, wherein a total bandwidthof channels in the first channel set is less than available transmissionbandwidth of a system, and wherein the first channel set comprises anavailable channel for the first STA to perform data transmission withthe AP; and receiving, by the first STA, a second frame, wherein thesecond frame is a response to the first frame.
 2. The method accordingto claim 1, wherein the second frame comprises a second channel set,wherein the second channel set comprises an available channel indicatedby the AP to perform data transmission with the first STA, and wherein atotal bandwidth of channels in the second channel set is less than theavailable transmission bandwidth of the system.
 3. The method accordingto claim 1, further comprising: receiving, by the first STA, a firsttrigger frame sent by the AP, wherein the first trigger frame indicatesa first operating channel of the first STA, and wherein the firstoperating channel is among the first channel set; and sending, by thefirst STA, data using the first operating channel.
 4. The methodaccording to claim 1, further comprising receiving, by the first STAusing the first operating channel, a physical layer protocol data unit(PPDU) sent by the AP.
 5. The method according to claim 2, wherein thesecond channel set is the same as the first channel set, or the secondchannel set is different from the first channel set.
 6. A datatransmission method comprising: receiving, by an access point (AP), afirst frame sent by a first station (STA), wherein the first framecomprises a first channel set, wherein a total bandwidth of channels inthe first channel set is less than an available transmission bandwidthof a system, and wherein the first channel set comprises an availablechannel for the first STA to perform data transmission with the AP; andsending, by the AP, a second frame, wherein the second frame is aresponse to the first frame.
 7. The method according to claim 6, whereinthe second frame comprises a second channel set, wherein the secondchannel set comprises an available channel indicated by the AP toperform data transmission with the first STA, and wherein a totalbandwidth of channels in the second channel set is less than theavailable transmission bandwidth of the system.
 8. The method accordingto claim 6, further comprising: sending, by the AP, a first triggerframe to the first STA, wherein the first trigger frame indicates afirst operating channel of the first STA, and wherein the firstoperating channel is among the first channel set; and receiving, by theAP, data sent by the first STA using the first operating channel.
 9. Themethod according to claim 8, further comprising: sending, by the AP, asecond trigger frame to a second STA, wherein the second trigger frameindicates a second operating channel for the second STA to perform datatransmission with the AP, and wherein the second operating channel andthe first operating channel do not overlap.
 10. The method according toclaim 6, further comprising sending, by the AP using the first operatingchannel, a physical layer protocol data unit (PPDU) to the first STA.11. The method according to claim 7, wherein the second channel set isthe same as the first channel set, or the second channel set isdifferent from the first channel set.
 12. A first station (STA)comprising: a memory storage comprising instructions; and one or moreprocessors in communication with the memory, wherein the one or moreprocessors execute the instructions to: send a first frame to an accesspoint (AP), wherein the first frame comprises a first channel set,wherein a total bandwidth of channels in the first channel set is lessthan available transmission bandwidth of a system, and wherein the firstchannel set comprises an available channel for the first STA to performdata transmission with the AP; and receive a second frame, wherein thesecond frame is a response to the first frame.
 13. The first STAaccording to claim 12, wherein the second frame comprises a secondchannel set, wherein the second channel set comprises an availablechannel indicated by the AP to perform data transmission with the firstSTA, and wherein a total bandwidth of channels in the second channel setis less than the available transmission bandwidth of the system.
 14. Thefirst STA according to claim 12, wherein the one or more processorsfurther execute the instructions to: receive a first trigger frame sentby the AP, wherein the first trigger frame indicates a first operatingchannel of the first STA, and wherein the first operating channel isamong the first channel set; and send data using the first operatingchannel.
 15. The first STA according to claim 12, wherein the one ormore processors further execute the instructions to receive a physicallayer protocol data unit (PPDU) sent by the AP using the first operatingchannel.
 16. The first STA according to claim 13, wherein the secondchannel set is the same as the first channel set, or the second channelset is different from the first channel set.
 17. An access point (AP)comprising: a memory storage comprising instructions; and one or moreprocessors in communication with the memory, wherein the one or moreprocessors execute the instructions to: receive a first frame sent by afirst station (STA), wherein the first frame comprises a first channelset, wherein a total bandwidth of channels in the first channel set isless than available transmission bandwidth of a system, and wherein thefirst channel set comprises an available channel for the first STA toperform data transmission with the AP; and send a second frame, whereinthe second frame is a response to the first frame.
 18. The access point(AP) according to claim 17, wherein the second frame comprises a secondchannel set, wherein the second channel set comprises an availablechannel indicated by the AP to perform data transmission with the firstSTA, and wherein a total bandwidth of channels in the second channel setis less than the available transmission bandwidth of the system.
 19. Theaccess point (AP) according to claim 17, wherein the one or moreprocessors further execute the instructions to: send a first triggerframe to the first STA, wherein the first trigger frame indicates afirst operating channel of the first STA, and wherein the firstoperating channel is among the first channel set; and receive data sentby the first STA using the first operating channel.
 20. The access point(AP) according to claim 19, wherein the one or more processors furtherexecute the instructions to: send a second trigger frame to a secondSTA, wherein the second trigger frame indicates a second operatingchannel for the second STA to perform data transmission with the AP, andwherein the second operating channel and the first operating channel donot overlap.
 21. The access point (AP) according to claim 17, whereinthe one or more processors further execute the instructions to send aphysical layer protocol data unit (PPDU) to the first STA using thefirst operating channel.
 22. The access point (AP) according to claim18, wherein the second channel set is the same as the first channel set,or the second channel set is different from the first channel set.